Telephone-exchange system



A; E. LUNDELL. TELEPHONE EXCHANGE SYSTEM. APPLICATION FILED OCT. I6. ISIS- all KH., ...Hr KY N\ A. E. LUNDELL. TELEPHONE EXCHANGE SYSTEM. APPLlcATloN FILED ocT. 16. 1-919.

1,41 0,766, Patented Mar. 2s, 1922.

' 2 SHEETS-SHEET 2.

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UNITED STATES PATENT orifice;

ALBEN E. LNDELL, or CHICAGO, ILLrNorS, ASSIGNoRTo WESTERN ELECTRICV COMPANY, iNCoRPoRATED, or NEW YCRK, .A CORPORATION or NEW YORK.

TELEPHONE- NCHANCE SYSTEM.

Specification of Letters Patent. y Patntjd wlan '28,

l Application filed October 1G, 1919. Serial No. 331,057.

To all whom it may concern.' y

Be it known that l, ALBEN E. LUNDELL, a citizen of the United States, residing at Ghicago, in the county ot Cook, VState ci' Illinois, have invented certainV new and useful lmprovements in Telephone-Exchange `Systems, oit which the following is a full, clear, concise, and exact description. f

This invention relates` to improvements in telephone exchange systems, and particularly to a circuit arrangement tor controlling the operation of the selector switches.

An object oi the invention is to increase the speed of f selection hy the automatic switches without sacrificing accuracy and also to reduce the amount of controlling equipment 'for measuring ott the travel of the switches. Heretofore, as shown tor cX- a-mple in the patent to Lundell No. 1,168,319, impulses were transmitted to the count-ing relays due to the shunting ot the stepping relay by a commutator brush passing vover the commutator plate, whic i plate had a ment for each line terminating .in the switch. These relays measured ott the travel of the selector and When a predetermined segment was reached, the corresponding relay operated to stop the switch atwhich time the talking brushesfwere'in ,Contact with the sired line. Y Y

In carrying out, this invention, instead oit providing a commutator segment tor each. line terminatingr in the switch, one segment is provided for every other line in one commutatorY plate and an additional commutator plate adjacent the iirst plate carries sepiments-il for the linesnot represented on the fi rst pl ze and an extra contactis provided on the key set which is closed if the digit ofthe called number is of a certain charactenior example, odd. As the commutator brush is travelw ing over the first named plate an impulse .is transmitted to the stepping relay of the sender for each segment encountered, this stepping relay operating the counting relays in succession, and when the last counting relay pair is reached and the fundamentar circuit opened, the selector stops if the digit is, for example,` even, but if odd, a circuit `prepared hy the said'eXtra contact is closed,

ncludmg the second commutator plate. This circuitprovides a substitute path to hold the selector power magnet energizedk until the sellector reaches thenext set of talking termina s.

The same arrangement may he applied to group selectiongthat is, it the tens digitot the called numher is odd, the selector is stopped when the last counting relay pair operates,` hut it the saiddigit is even, a subf stitute circuit is closed, including the extra group commutator plate, and aneXtraf contact of thetens keys to maintain power` applied to the selector until it reaches the hcginning ot the lsubsequent' group.

Referring toy the drawings, Figs. Il. and 2 illustrate diagramniatically a circuit arrangement for carrying out the invention applied to a semiautomatic telephone system,

`The selector switches employed in this system may be of the type disclosed in the patent to Craft and Reynolds No.1,123,696, and a complete operating circuit for` these switches is disclosed in said Patent No. 1,168,319. The registering and controlling devices ot theahove -mentioned patent to Lundell may also he employed in this system. ln this invention sequence switches are cmployed thaty are similar in; construction to that disclosed in the patent to Reynolds and Baldwin No. 1,127,808,y and theyare similail in operation and function to that disclosed in the patent to McBertyrNo. 1,125,579.

Since thev general operation and arrange'- inent, as 4disclosed in the above mentioned patents, does not 'form a part of this invention, the greater part of' it has been omitted and only sufficient portions thereof have been disclosed to set forth their relation. to this invention. Y u

It is to be understood that, a single selector switch has heen shown and described in this application, in actual practice'a series ot such selectors may he `employed. The switch shown in `this system would he classed as an arrangement, butin order t0 bring out the invention more clearly it has 4loeenshown conn.ecteddirectly with the operators cord circuit in the saine manner in which a disalthou only a final selector in such trict switch Wouldhave been connected.V It

is Vlcelieved `that by describing the various operations necessary for setting up a con.-

nection between the `callingSuhscribers station indicated at A and the calledy subscribers station indicated at B, the invention will be readily understood. Howe-rer, only the operations most intimately related to the invention will be described, and as to the remaining operations, reference may be had to the above mentioned patents.

When the subscriber at A removes his receiver from the switchhook, a circuit is coinpleted from. battery through the lett-hand windingot line relay 110, back contact and outer left-hand armature of cutoiil relay 111, the subscribers apparatus at A, the back contact and inner left-hand armature of relay 111, and right-hand winding of line relay 110, to ground. Line relay 1]() attracts its armature and thereby completes a local circuit Jfor lighting the lamp 113. The operator observing that the lamp is lighted, inserts the answering plug` 114 ot a cord'circuit 115 in the answering jack of the calling line. The cutoff relay 111 and relay 117 are thereupon energized in series over a circuit extending from battery, winding el cutot'r` relay 111, sleeve ot jack 116, sleeve of plug 114 and winding of relay 117, to ground. These relays attract their armatures and the cutoff relay 111 interrupts the energizing circuit ot the line relay 11,0 which on the retraction ot its armature interrupts the circuit of the lamp 113. The relay 117 on attracting its armature coinpletes a circuit from battery, power magnet of sequence switch 100, upper leftehand sequence switch contact 118, front contact and armature of relay 117, to ground, to move the sequence switch 100 out of position 1 into position 2, under the control ot its master contact 120. In position 2 otV sequence switch 100, a circuit is completed from battery, relay 210,` upper sequence switch contact 211, conductor 212, lower quence switch contact 122 to ground. Relay 210 is energized and completes a locking circuit for itself from battery, the lower sequence switch contact 211, armature and front contact of relay 210. conductor 215. upper sequence switch contact 122, to ground. The operation of relay 210 cornpletes a circuit 'for sequence switch 200 'from battery, sequence switch magnet 200, upper right-hand sequence switch contact 216l 'trent contact and lett-hand armature oi relay 210, to ground, to more the .sequence switch 200 out o1 position 1 into position 3, under the control of its master contact 219. n

lVhileV theseoperations are taking place, the operator is connected with the calling subscriber through a listening key in an associated circuit` arrangement, not shown, and she' ascertains therebythe nuinber of the desired` line. It` will be assumed that the number wanted by the calling subscriber is29. The operator thereupon depressies the keys 2 and 9, shown on the rows of ,keysv C and "D respectively.l Ipv de pressing key No. 2 or any even numbered key in row C, contact 247 remains open. .lit an odd numbered key is depressed, contact 247 closes. Contact 24? is controlled in the same manner by the depression oi: thc odd numbered keys in set l).

After depressingv the keys No. 2 oi' the tens group C and No. S) ot the units group D, the operator depresses the starting key 225 which closes a circuit Ytor moving the sequence switch 200 out of position 3 and into position 4. This circuit may be traced from battery, sequence switch 201), lower sequence switch contact 216, starting key 225, to ground.

lVith the sequence switch 200 in position 4 and sequence switch 100 in position 2. a fundamental circuit is established from battery, relay 125, lower sequence switch contact 128, conductor 129, contact 228, stepping relay 229, the sequence switch contact 230, conductor 2531, sequence switch Contact 130, to ground. Relay 125 is energized and establishes a locking circuit lor itself by way of its left-hand armature and Afront contact and over the cirvuit yinst raced. The operation o1 relay 125 completes a circuit from battery, sequence switch magnet 100, conductor 134, upper sequence switch contact 135, 'front contact and right hand armature oli relay 125, to ground, for moving the sequence switch 100 out ot position 2 and into position R. ln position 3 ot sequence switch 100 a circuit' is completed Yfrein battery, up-drive power magnet 139, lower right-hand sequence switch contact 135, front contact and right-hand armature of relay 125, to ground. This circuit energizes the up-driye power magnet which elerates a brush sha'lt 140 of the switch E. the brush shaft is elevated, the brushes 141, 142, and 144 are brought into engage ment with their respective commutators 145, 146, 147 and 148, andas the brush 141 passes over the conducting segments of thc coinniutator 145. a circuit is completed from battery, relay 125, conductor 129, upper right-hand sequence switch contact ,128, conductor 150, cornmutator 145, and brush 141., to ground. As the switch is advanced this circuit acts as a short circuit for the step ping relay 229, which is thereby permitted to alternately energize and deenergize.

When the stepping relay was originally energized, a circuit was completed trom battery, counting relay 233, armature and back Contact oit counting relay 234, key No. 2 in the tens group, lett-handv sequence switch contact 285, conductor 236, armature and front contact ot stepping relay 22S), to ground. This circuit energized relay which completed a: locking circuit for itself and a circuit for relay 234 'from battery, windings" of relays 238 and 234, armature and front COntact ot. relay 233, right-hand l ll 0 Cfr lay 229 has been deenergized because relay 234 is shunted by the ground at its back contact. When stepping relay 229 deenergizes it removes the groundi'rom the conductory236, when said circuit energizes relay 234 and locks up the two relays 233 and 234V inV series. The stepping relay `229 is again energized when the brush 141 passes off the iirst conducting segment of commutator 145 and a circuit is now completed from relay 238 by way of the armature and iront contacto'f relay 234to the key No. 2 in group C. As soon as the brush 141 comes in contact with the second conducting segment of commutator 145, stepping relay 229 is again deenergized. This time the deenergization of stepping relay 229 causes the relay 239 to be energized and relays 238 and 239 to be locked up in the. same manner as were relays 233 and y234. The energization of relay 239 opens thefundamental circuit at con-f tact 228 and the relay 125 will therefore be permitted to deenergize as soon as brush141 has passed off the second conducting segment of commutator 145 which controls the switch actuation from 2O to 39, the first conducting segment controlling said actuation from 0 to 19. In deenergizing, relay 125 breaks at its right-hand armature and front contact, the circuit `previously maintained or power magnet 139, thus bringing the switch brushes to rest. v

The operation of relay 239 also completes a circuit from battery, sequence switch 200, outer armature and front contact of relay 239, left-hand sequence switch contact 237, to ground, for moving the sequence switch 200 out of 'position 4 into position 6. The counting relays are thereby unlocked and de energized and the fundamental circuit is again closed at contact 228. The deenergization of relay 125 completed a circuit trom battery, sequence switch 100, ksequence switch contact 152, outer left-hand armaturc and back contact of relay 153, righthand armature and back contact of relay 125, to ground, to move sequence Switch 100r out of position 3 into position 6. K

With sequence switch 200 in position 6 and sequence switch 10() in position 6, the fundamental circuit is again established; relay 125 is energized and locked up through the same circuit as before, and a circuit completed from battery, sequence `switch 100, conductor 134, upper sequence switch contact 135, right-hand armature and front contacty of relay 125, to ground, to move sequence switch 100 into position y7.

As the unitV key selected in this case was assumed to be an odd number (9), the selector operates in arnanner different from that described as taking place when an'even number was selected. The stepping relay 229 is alternately deenergized and energized in the same manner as beiore but the deenergization is takingV 'place over a different shunt circuit which may be traced from battery, left-hand armature and front contact of relay 125, conductor '129, left-hand se-- quence switch Contact 128, conductor 154, commutator 147, brush 143, to ground." The counting relays are locked up in succession beginning with the fifth `set as the brush143 passes over the conducting segments of the commutator 147. lVhen thefiith conducting` segment in the third group on commuta`- tor 147 is passed by the brush 143, the last set of counting relays 238 and 239 are locked up and the fundamental circuit is broken. Relay 1 25 is deenergized as before. The brushes 164, 165, 172 on the brush shaft 140 have by this time reached the ninth terminal in the bank F. Due to the fact that the contact 243 isclosed in the case assumed, the energizing circuit for 4the powermagnet 139 is not broken at this time but maintained until the brushes reach the tenth terminal corresponding to the No. 9 unit key. Power magnet 139 is maintained energized over a circuit Jfrom battery, power vmagnet 139, lowery sequence switch `contacts 135, front contact and inner left-hand armature `of relay 153, to ground.` The relay 153 is energized at this time by a circuit from battery, relay 153, conductor 242, contact 243, right-hand sequence switch contact 245, conductor 246, left-hand sequence switch contact 158, commutator 148 and brush 144,to` ground. l e p K' VVThe relation or', the lconducting lsegments on the commutator 148 to the conductingV i segments on the commutator`147 is such as to vcomplete this energizing circuit for relay 153 before relay 125 is permitted to deenergize, thusmaintaining the circuit'for moving the sequence switch 100 out ot position 7 open atthe outerleft-hand armature and back contact of relay 153. This circuit "for sequence switch 100 wouldordinarily be completed at the righthand armature and back contact ci relay 125 as soon asit'is deenergized. In this case, however, there- 4 lay 153 is maintained' energized over a lockf ing circuit from battery, winding, righthand` armatureand front contactof relay 153, sequence switch contact .159,lef-t sequence switch AContact 158,]commutator 148, and brush 144, to ground.` The position of `the conductingsegments on ,y commutator 148 in relation to brush 144 is such asto maintain this locking circuit and keep the switch moving until its brushes reach the ktenth set of terminals onV the bank F. When the brushes are accurately located on the terminals, this locking circuit` isA broken and relay 153 permitted to deenergize. The switchis then 'stopped by the breaking of the iio ias

branch of the energizing circuit for; the power magnet 139 maintained throughthe inner left-hand armature and front contact of relay Then relayT 289 was energized a circuit was completed trom battery, sequence switch 200, outer armature and :trent contact of relay 239, left-hand contact ot sequence switch contact 237, to ground, for moving sequence switch 200 from position 6 .into position 16. lWhen relay 153 deenergizes, a circuit is completed from battery, scquence switch 100, sequence switch contact 152, outer left-hand armature and back contact of relay 158, right-hand armature and back contact of relay 125, to ground, for moving the sequence switch out of position 7 into position 11. lith the sequence switch 200 4in position 16 and the sequence switch 1,00 in position 11. the locking circuit for relay 210 is broken at lower sequence switch contact 211. The deenergization o'f relay 210 completes a circuit from battery, sequence switch power magnet 200, left-hand sequence switch contact 216, letthandl armature and back contact oil relay 21.0, to ground, for moving sequence switch 200 out of position 16 into position 18. In position18 ofsequence switch 200, a circuit vis completed from batteryseqnence switch 100, lower sequence switch contact 118` conductor. 24:8, sequence switch contact 2419, to ground, for moving the sequence switch 100 out of position 11 into position 16. In position 16 of sequence switch 100, the talking conductors and 161. are extended through sequence switch contacts 162 and 163, brushes 164 and 165, terminals 166 and 1.67 and line conductors 168 and 169 leadingto the calledsubscribers station at B, In position 16 ot' sequence switch 100, a busy test ground through resistance 170 and se quence switch contact 171 is placed on the test brush 172 and terminal 178 to protect the line from being seized by another selector switch.

At the close of the conversation, the supervisory relays 17.4.- and 175 operate in the well known manner to indicate the termination of the call to the operator. The operator thenl removes the plug 11114 from jack 116 and causes the relay 117 to be deenergized. At the retraction of the armature of relay 117, a circuit is completed from battery, sequence switch 100, upper right-hand sequence switch contact 118, armature and back contact4 of relay 117, to ground, to move the sequence switch 100 out of position 16 into position 18. In position 18 of sequence switch 100, a circuit is completed from battery, down-drive power magnet 176, sequence switch contact 178, to ground, to drive the selector back to normal position. When the selector has been restored to normal, a circuit is completed from battery, sequence -switch 100, conductor 1841;, sequence switch.

contact 179, commutator segment 180, brush. 141-1, to ground, to move the sequence switch .10() from position 18 back to normal position. The sequence switch 260 and key sets C and l) are restored to normal position in the well known manner shown in the above mentioned patents.

Let it be assumed that the tens digit was instead of 2. In this case, the contact 2:17 would be closed. Two sets oit counting relays would be locked up and in response to the two deenergizations oi" the stepping relay Q29, the brushes lieti, 142, 149), 1117-1 would be stepped to the beginning ot' the third group. ln this position brush 1:12 would engage the second conducting segrment oitl the commntator 146 and, contact 2417 being closed, the. rip-drive magnet 139 would continue to operate to move the brushes over the third group and to the beginning ot the fourth group. it this time brush 142 will pass trom said second con ducting segment ol commutat/nf 1/16 and the brushes will come to rest.

That this arrangement is advantageous is readily seen, as the equipment oi counting relay pairs is only halt' oi" what is ordinarily required and the speed oit the selector switches may be considerably increased without impair-ing accuracy ot selection` duc to the fact that a selector can advance a distance equal to the two groups oitl individual line contacts for every operation of a counting relay pair.

Tha-t is claimed is:

1. In a telephone system, incoming lines. outgoing line contacts` a switch for associating said incoming lines with any one of' said contacts, a controlling device :for directing the switch to an alternate contact, and means to direct the switch to an intcrmcdiate contact that lies beyond the last alternate contact reached` at 'the termin ati on o? any paiticnla-r selecting movement ot the switch.

2. In a telephone system, incoming lines, outgoing line contacts, a switch for associating said incoming lines with any one oli said contacts, a commntator segmentrepresenting every alternate contact, means cooperating with said commutator segment to direct the switch to a predetermined one ot said alternate contacts, a second commntator segment representing every other contact, and means cooperating with said second commutator segment to continue to direct the switch to a contact located beyond the alternate Contact to which the switch vas primarily directed.

8. In a telephone system, incoming' lines, outgoing line contacts, a switch for associating said incoming lines with any one of said contacts, a commutator segment representing every alternate contact, a switch 'l te the intermediate contact vlocated beyond the last alternate contact selectedf ln a telephone s; i alternate and int/armed linecontacts,

"enh any one ot said contacts, means to rect the switch to any one ot the alternate contacts,V meansto direct the switch' to the l ast alternate contact in any particular selecting movement, and means to continue to direct the switch to the next intermediate contact at the termination ot saidparticu lar selecting movement. i

ln a telephone system, incoming lines, outgoing line contacts, a switch tor associating said incoming lines with any one ot' said centacts, a commutator having segments representing every alternate contact, selectively operable counting relay sets repr senting every alternate cont-act, means cooperating with said commutator segments and counting relays tc `direct the switch to the alternate contact corresponding to the selected counting relay set, and vmeans to continue to direct the switch to another contact adjacent the alternate contact selected.

6. ,ln a telephone system, incoming lines, outgoing line contacts, a switch tor asscciating said incoming lines with any one oit said contacts, a commutator having segments representing every alternate contact, counting relay sets representing every alternate contact, selecting means ior said countelay sets,` means coopc ating with said commutator and said counting relays to direct the switch to the alternate contact corresponding to the selected counting relay and means to continue to direct the switch to another contact adjacent the alternate contact selected.

T. ln a telephone system, incoming lines, outgoing line contacts, a switch tor associatingl said incoming lines` with any one of said contacts, a commutator having segments tor every alternate contact, counting relay sets 'For said alternate contacts, selecting means tor said counting relay sets so arranged as to select the same set ot counting relays tor a corresponding alternate contact and the succeeding` intermediate contact, means cooperating with said commutator and said counting relays to direct the switch to the alternate contact corresponding to the selected counting relay set, and means to continue to direct the switch to the intermediate contact succeeding the alternate'contact selected.

itch tor associating! said inca img lines 8. ln a telephone system, incoming lines, alternate and intermediate line contacts,` a switch. for associating said incoming lines with any one otsaid contacts, means to direct the switch to the lasty alternate Contact ,in any particular selecting movement, means to continue to direct the switch to the succeeding intermediate contact at the termination of said selecting movement, and a selecting means toi' saiddirective means.y f

9.Y In a telephone system, incoming lines,

alternate and intermediate line contacts,

switch for associating said incoming lines with any one of said contacts, means to direct the switch to a predetermined alternate contact in any particular selecting movement, means to continue to direct the switchy to the succeeding intermediate contact, and a selecting means common to said directive means for jointly controlling the same.

10. In a telephone exchange system, a switch, sets ot line terminals therein, a plate thereon having a contact Afor every other set ot' terminals, a number of pairs ot counting relays equal to the number of contacts on said plate, a key set having a contact closed when the digit key operated corresponds to a line terminal set not represented on said plate, a circuit for operating said relays in succession to measure oil' the travel of the switch, and a circuit including said key set contact for continuing the travel of the switch to the next set of line terminals after the last counting relay pairhas operated.

l1. In a telephone exchange system, a

switch, sets of vline terminals therein di-y having a contact closedwhen the digit key operated corresponds to a line set not represented on said plate, a circuit for operating said relays in succession to measure oil' the travel of the switch, and a circuit including said key set Contact for continuing the travel of the switch to the next group ot line contacts after the last counting relay pair has operated, v

12. In a telephone exchange system, a switch, sets of line contacts thereon, a commutator plate having a segment Jfor every other set of terminals, pairs of counting relays equal in number to the number ot segments, a key set having a contact closed whenthe digit key operated corresponds to a terminal set not represented on the commutator, a fundamental circuit for maintaining power applied to the switch, said relays controlling said circuit and opening the same when the last of said relays operates,

switch te continue its travel to the next line terminal set.

13. In iy telephone system, telephone lines, a switch for interconnecting said lines, a key Set for controlling said switch, an extra contact on said key set responsive in its actuation to the lactuation of alternate keys in said set, and means responsive to the actuation of said extra contact for causing said switch to move'an additional'step.

14. In a telephonesystem,incoming lines, outgoing line contacts, a switch for associatingv said incoming lines with any one of said contacts,a controlling device fordifrecting, the Switch to one of said contacts and means to direct the switch to another contact that lies beyondy the contact reached at ALBEN E. LUNDELL. 

